Re: Static Phase Converters

>MUCH better WAY! The "old 3Ø motor" is used as a "rotary
>transformer".
>Sound technology. Results is true 120° phase-angle difference,
>whereas the
>static type won't give you equally-spaced nor amplitude "phases".

This is not correct. A 3 phase motor run as an 'idler' motor on the line
has 2 phase locked to the power line that is driving it. You get a
'lumpy' 3 phase output. instead of 0-120-240 you have 0-180-240.

For most things like a mill or lathe it works fine. For sensitive things
like surface grinders you will see ripple patterns in the work.

If you use a motor-generator set, then you can get real 3 phase, but
that is a very expensive way to do it.

A 'static phase convertor' is nothing more than a starting capacitor in
a box- wildly expensive for whats in the box. You can make one for under
$20 eaisly.

Much better is to get a VFD- a variable frequency drive. These
electronic boxes generate a real 3 phase, and provide variable speed
control. They can now be bought for arouund $100 for 1/2-1 hp Machines.

ron ginger